66605256247 has 8 divisors (see below), whose sum is σ = 66717809280. Its totient is φ = 66492786360.

The previous prime is 66605256241. The next prime is 66605256281. The reversal of 66605256247 is 74265250666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66605256247 - 2²³ = 66596867639 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66605256247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66605256241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1701222 + ... + 1739932.

It is an arithmetic number, because the mean of its divisors is an integer number (8339726160).

Almost surely, 2^66605256247 is an apocalyptic number.

66605256247 is a deficient number, since it is larger than the sum of its proper divisors (112553033).

66605256247 is a wasteful number, since it uses less digits than its factorization.

66605256247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41573.

The product of its (nonzero) digits is 3628800, while the sum is 49.

The spelling of 66605256247 in words is "sixty-six billion, six hundred five million, two hundred fifty-six thousand, two hundred forty-seven".